You have a Cleric creature card in hand with mana value 3 or less.
You have enough mana to cast the Cleric card in hand.
Steps
Cast any Cleric with mana value three or less from your hand by paying its mana cost.
The Cleric enters the battlefield as a copy of Orah due to Infinite Reflection.
Put the Cleric into your graveyard due to the legend rule.
The Cleric dies, triggering itself and Orah.
Resolve the Orah trigger, returning the Cleric from your graveyard to the battlefield.
Repeat from step 2 an arbitrarily large amount of times.
Once you have a large amount of triggers on the stack, you may instead choose to put Orah into your graveyard due to the legend rule, and return all Clerics with mana value three or less from your graveyard onto the battlefield.
Results
Infinite death triggers.
Infinite ETB.
Infinite LTB.
Return all Clerics with mana value three or less from your graveyard to the battlefield.